This page answers one size only: flooring for a room 15 feet by 12 feet. The answer below is for that size only. To change the room size, waste percentage, or carton coverage, use the Flooring Calculator.
Flooring for a 15 by 12 ft room: summary
| Item | Value |
|---|---|
| Room length | 15 ft |
| Room width | 12 ft |
| Room area | 180 sq ft |
| Waste allowance | 10% (18 sq ft) |
| Order area | 198 sq ft |
| Carton coverage used | 22 sq ft per carton |
| Cartons needed | 9 cartons |
Worked example in full
Step 1 — Room area: 15 ft × 12 ft = 180 square feet.
Step 2 — Waste: 180 sq ft × 10% = 18 square feet.
Step 3 — Order area: 180 sq ft + 18 sq ft = 198 square feet.
Step 4 — Cartons: 198 sq ft ÷ 22 sq ft per carton = 9 cartons exactly, so no rounding up is needed at this carton size.
Answer for this size only: a 15 by 12 ft room needs 180 square feet of flooring, 198 square feet including 10% waste, and 9 cartons at 22 square feet per carton. This result was verified against the Flooring Calculator using length 15 ft, width 12 ft, carton coverage 22 sq ft, and waste 10%.
Frequently asked questions
Is 9 cartons the answer for any room?
No. It is the answer for a 15 by 12 ft room with 10% waste and 22 square feet per carton only. A different room size, waste percentage, or carton size gives a different answer.
What if my cartons cover a different area?
Divide the order area, 198 square feet for this room, by your carton coverage, and round up to the next whole carton. The Flooring Calculator lets you change the carton coverage.
Why include waste?
Waste covers cuts at edges and around obstacles, plus damaged or spare pieces. The calculator lets you change the waste percentage for your room shape and pattern.
Method note
This is a planning calculation for the stated room size only. It assumes a rectangular room with no deductions for fixtures or openings. Measure your own room, deduct any areas you will not floor, and confirm carton coverage with your supplier before ordering.